人参皂苷Rg1、Rb1抗Aβ人血管内皮细胞损害作用的研究

目的:探讨人参皂苷Rg1、Rb1对β-淀粉样蛋白(Aβ)诱导人脑血管内皮细胞增殖抑制情况的影响。方法:将人脑血管内皮细胞分为对照组、Aβ1-42组(20μmol·L^-1)、低人参皂苷Rg1组(20μmol·L^-1 Aβ1-42+Rg1 0.1μmol·L^-1)、中人参皂苷Rg1组(20μmol·L^-1 Aβ1-42+Rg1 1μmol·L^-1)、高人参皂苷Rg1组(20μmol·L^-1 Aβ1-42+Rg1 10μmol·L^-1)、低人参皂苷Rb1组(20μmol·L^-1 Aβ1-42+Rb1 0.1μmol·L^-1)、中人参皂苷Rb1组(20μmol·L^-1 Aβ1-42+Rb1 1μmol·L^-1)、高人参皂苷Rb1组(20μmol·L^-1 Aβ1-42+Rb1 10μmol·L^-1)。用MTT检测各组细胞增殖能力,Western-blot检测各组细胞中PCNA、Ki67、COX-2蛋白表达情况,ELISA法检测各组细胞中IL-1、TNF-α水平。结果:与对照组相比,Aβ1-42组细胞的增殖率、PCNA、Ki67蛋白表达显著降低(P<0.05),COX-2、IL-1、TNF-α水平显著升高,与Aβ1-42组细胞相比,低、中、高人参皂苷Rg1和低、中、高人参皂苷Rb1组细胞的增殖率、PCNA、Ki67蛋白表达显著升高(P<0.05),COX-2、IL-1、TNF-α水平显著降低(P<0.05)。结论:人参皂苷Rg1、Rb1可能是通过促进增殖蛋白及抑制炎症因子表达来改善Aβ导致的人脑血管内皮细胞增殖抑制。

人参皂苷Rg1、Rb1抗转基因斑马鱼模型的Aβ血管损害作用

目的探究人参皂苷Rg1、Rb1对β-淀粉样蛋白(Aβ)导致转基因斑马鱼模型的血管损害作用的保护机制。方法选择正常健康转基因斑马鱼15尾,使用Aβ溶液诱导血管损伤转基因斑马鱼45尾,分为模型组、人参皂苷Rg1组和人参皂苷Rb1组各15尾。人参皂苷Rg1组和人参皂苷Rb1组分别使用20 mg/kg的Rg1、Rb1处理;检测各组转基因斑马鱼的血管长度和血管面积;使用ELISA检测各组转基因斑马鱼的血清中活性氧(ROS)、超氧物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力;使用Western blot检测各组斑马鱼转化生长因子β1(TGF-β1)、Smad2、Smad3及血管内皮生长因子(VEGF)表水平。结果与对照组比较,模型组血管长度、血管面积、SOD、GSH-Px水平和VEGF蛋白表达水平显著降低,ROS水平、TGF-β1、Smad2、Smad3蛋白表达水平显著升高,差异有统计学意义(P<0.05);相比模型组,人参皂苷Rg1组和人参皂苷Rb1组斑马鱼血管长度、血管面积、SOD、GSH-Px水平和VEGF蛋白表达水平显著升高,ROS水平、TGF-β1、Smad2、Smad3蛋白表达水平显著降低,差异有统计学意义(P<0.05)。结论人参皂苷Rg1、Rb1通过降低氧化应激及炎症反应并调节TGF-β1/Smads通路实现减轻Aβ对血管的损害。

Intracerebroventricular transplantation of human amniotic epithelial cells ameliorates spatial memory deficit in the doubly transgenic mice coexpressing APPswe and PS1△E9.deleted genes

Background Human amniotic epithelial cells （HAECs）, which have characteristics of both embryonic and pluripotent stem cells, are therefore a candidate in cell therapy without creating legal or ethical problems. In the present study, we aimed to investigate the effects of intracerebroventricular transplantation of HAECs on doubly transgenic mice of Alzheimer＇s disease （AD） coexpressing presenilin-1 （PS1） and mutant Sweden amyloid precursor protein （APPswe） genes. Methods The offspring mice genotypes were detected using PCR identification of APPswe and PS1 gene. The doubly transgenic （TG） mice （n=20） and wild-type （WT） mice （n=20） were randomly divided into two groups respectively： the transplantation group treated with HAECs and the control group with phosphate buffered saline. Six radial arm water maze test was used to assess the spatial memory in the TG and WT mice. Amyloid plaques and neurofibrillary tangles were analyzed using congo red and acid-silver methenamine staining respectively. was used to track the survival of HAECs. Immunohistochemistry was used octamer-binding protein 4 （Oct-4） and Nanog in the HAECs. High performance measure acetylcholine in hippocampus. The density of cholinergic neurons in hippocampus was measured using acetylcholinesterase staining. Immunofluorescence cytochemistry to determine the expression of quid chromatography was used to basal forebrain and nerve fibers in Results Amyloid deposition occurred in hippocampus and frontal cortex in the double TG mice aged 8 months, but not in WT mice. The results also showed that transplanted HAECs can survive for at least 8 weeks and migrate to the third ventricle without immune rejection. The graft HAECs can also express the specific marker Oct-4 and Nanog of stem cell. Compared with the control group, transplantation of HAECs can not only significantly improve the spatial memory of the TG mice, but also increase acetylcholine concentration and the number of hippocampal cholinergic neurites. Conclusions These results demonstrate that intracerebroventricular transplantation of HAECs can improve the spatial memory of the double TG mice. The higher content of acetylcholine in hippocampus released by more survived cholinergic neurites is one of the causes of this improvement.